US5034551A - Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds - Google Patents

Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds Download PDF

Info

Publication number
US5034551A
US5034551A US07/512,690 US51269090A US5034551A US 5034551 A US5034551 A US 5034551A US 51269090 A US51269090 A US 51269090A US 5034551 A US5034551 A US 5034551A
Authority
US
United States
Prior art keywords
distannoxane
tetra
diacyloxy
hydrocarbyl
sucrose
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US07/512,690
Other languages
English (en)
Inventor
Nicholas M. Vernon
Robert E. Walkup
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tate and Lyle PLC
Noramco LLC
Original Assignee
Noramco LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
US case filed in International Trade Commission litigation Critical https://portal.unifiedpatents.com/litigation/International%20Trade%20Commission/case/337-TA-604 Source: International Trade Commission Jurisdiction: International Trade Commission "Unified Patents Litigation Data" by Unified Patents is licensed under a Creative Commons Attribution 4.0 International License.
First worldwide family litigation filed litigation https://patents.darts-ip.com/?family=24040135&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=US5034551(A) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Noramco LLC filed Critical Noramco LLC
Priority to US07/512,690 priority Critical patent/US5034551A/en
Assigned to NORAMCO, INC., A CORP. OF GA reassignment NORAMCO, INC., A CORP. OF GA ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: VERNON, NICHOLAS M., WALKUP, ROBERT E.
Priority to GR910100149A priority patent/GR1002083B/el
Priority to NZ237765A priority patent/NZ237765A/xx
Priority to PH42296A priority patent/PH27407A/en
Priority to IL9789191A priority patent/IL97891A/en
Priority to AU75377/91A priority patent/AU631062B2/en
Priority to JP3113708A priority patent/JP2882548B2/ja
Priority to YU71591A priority patent/YU48759B/sr
Priority to TR41091A priority patent/TR25514A/xx
Priority to ZA912995A priority patent/ZA912995B/xx
Priority to SU914895127A priority patent/RU2036197C1/ru
Priority to DK91303565.5T priority patent/DK0455390T3/da
Priority to DE69113106T priority patent/DE69113106T2/de
Priority to FI911941A priority patent/FI97886C/fi
Priority to IE134391A priority patent/IE68437B1/en
Priority to CA002040933A priority patent/CA2040933C/en
Priority to KR1019910006388A priority patent/KR0176972B1/ko
Priority to PT97432A priority patent/PT97432B/pt
Priority to EP91303565A priority patent/EP0455390B1/en
Priority to ES91303565T priority patent/ES2080895T3/es
Priority to NO911590A priority patent/NO180009C/no
Priority to MX25476A priority patent/MX165090B/es
Assigned to MCNEIL-PPC, INC. A NJ CORPORATION reassignment MCNEIL-PPC, INC. A NJ CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: NORAMCO, INC., A GA CORPORATION
Publication of US5034551A publication Critical patent/US5034551A/en
Application granted granted Critical
Priority to TW080106687A priority patent/TW197443B/zh
Assigned to TATE & LYLE PUBLIC LIMITED COMPANY reassignment TATE & LYLE PUBLIC LIMITED COMPANY ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MCNEIL-PPC, INC.
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F7/00—Compounds containing elements of Groups 4 or 14 of the Periodic Table
    • C07F7/22—Tin compounds
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
    • C07H13/00—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids
    • C07H13/02—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids by carboxylic acids
    • C07H13/04—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids by carboxylic acids having the esterifying carboxyl radicals attached to acyclic carbon atoms
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F7/00—Compounds containing elements of Groups 4 or 14 of the Periodic Table
    • C07F7/22—Tin compounds
    • C07F7/2224—Compounds having one or more tin-oxygen linkages
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
    • C07H13/00—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids
    • C07H13/02—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids by carboxylic acids
    • C07H13/08—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids by carboxylic acids having the esterifying carboxyl radicals directly attached to carbocyclic rings

Definitions

  • sucrose contains three primary hydroxyl groups and five secondary hydroxyl groups. Therefore, when it is desired to prepare derivatives of sucrose involving reaction of the hydroxyl groups, it can be a major synthesis problem to direct the reaction only to the desired hydroxyl groups.
  • the artificial sweetener 4,1',6'-trichloro-4,1',6'-trideoxygalacto-sucrose (“sucralose”) is derived from sucrose by replacing the hydroxyls in the 4, 1', and 6' positions with chlorine. (In the process of making the sweetener, the stereo configuration at the 4 position is reversed - hence the compound is a galactosucrose.) This compound and methods for synthesizing it are disclosed in U.S. Pat.
  • Navia disclosed that a suitable di(hydrocarbyl)tin-based species, such as dibutyltin oxide, dioctyltin oxide, dibutyltin dimethoxide, or the like, could be combined with a hydroxyl group-containing compound such as a monohydric alcohol or a simple phenol in such a way as to produce a reactive distannoxane intermediate [i.e., a 1,3-di(hydrocarbyloxy)-1,1,3,3-tetra(hydrocarbyl)distannoxane], which could then be reacted with sucrose to afford a 1,3-di-(6-O-sucrose)-1,1,3,3-tetra(hydrocarbyl)distannoxane. Navia also described the ready preparation of sucrose-6-esters by the treatment of these organotin-sucrose adducts with a suitable acylating agent in an appropriate solvent or solvent mixture.
  • Neiditch et al. comprises reacting sucrose with a di(hydrocarbyl)tin oxide in an inert organic vehicle for a period of time and at a temperature sufficient to produce a 1,3-di-(6-O-sucrose)-1,1,3,3-tetra(hydrocarbyl)distannoxane.
  • the 1,3-di-(6-O-sucrose)-1,1,3,3-tetra(hydrocarbyl)distannoxane thus produced is reacted with an acylating agent at a temperature and for a period of time sufficient to produce a sucrose-6-ester.
  • a di(hydrocarbyl)tin oxide such as a dialkyltin oxide
  • a dihydric alcohol, alkanolamine, or an enolizable ⁇ -hydroxy ketone i.e., an ⁇ -hydroxy ketone that is capable of enolization to an enediol
  • an inert organic reaction vehicle with removal of water by azeotropic distillation and at a temperature and for a period of time sufficient to produce a cyclic adduct of said diaklytin oxide and said dihydric alcohol, alkanolamine, or enolizable ⁇ -hydroxy ketone
  • Step (b) reacting said cyclic adduct product of Step (a) with sucrose in an inert organic reaction vehicle in which sucrose has an appropriate degree of solubility, such as a dipolar aprotic liquid, at a temperature and for a period of time sufficient to produce a 6-O-[dihydrocarbyl(hydroxy- or amino- or oxohydrocarbyl)stannoxyl]sucrose; and
  • Step (c) reacting the product of Step (b) with an acylating agent to produce a sucrose-6-ester.
  • the reaction mixture containing the sucrose-6-ester also contains as a byproduct a 1,3-diacyloxy-1,1,3,3-tetra(hydrocarbyl)distannoxane or distannoxane diester ("DSDE").
  • S-6-E sucrose-6-ester
  • DSDE 1,3-diacyloxy-1,1,3,3-tetra(hydrocarbyl)distannoxane or distannoxane diester
  • the invention provides a process which comprises extracting a DSDE from a mixture containing a DSDE, a sucrose-6-ester, and a polar aprotic solvent, which process comprises the steps of:
  • the presence of a small amount of water in the extraction mixture serves to enable or to significantly enhance the partitioning of the DSDE into said organic solvent while the S-6-E remains dissolved in the polar aprotic solvent, so that the DSDE can be extracted almost quantitatively by the said organic solvent while the sucrose-6-ester remains in solution in the polar aprotic solvent.
  • the organotin-mediated regioselective 6-position acylations of sucrose to produce sucrose-6-esters are described in the Navia, the Walkup et al., and the Neiditch et al. patent applications described above.
  • the utility of sucrose-6-esters in a process for producing the artificial sweetener 4,1',6'-trichloro-4,1',6'-trideoxygalactosucrose is described, for example, in U.S. application Ser. No. 382,147, for IMPROVED SUCROSE-6-ESTER CHLORINATION, filed July 18, 1989, by R. E. Walkup, N. M. Vernon, and J. L. Navia, and assigned to the same assignee as this application.
  • the partitioning of the DSDE byproduct, resulting in situ after sucrose acylation, between two organic solvent phases, said partitioning being promoted by the addition of a small amount of water has no literature precedent.
  • the invention comprises a process for extracting a distannoxane diester from a mixture containing the same along with a sucrose-6-ester and a polar aprotic solvent, by contacting said mixture with an organic solvent that is substantially immiscible with water and in which the DSDE is soluble, in the presence of a small amount of water.
  • the mixture containing the DSDE, S-6-E, and polar aprotic solvent can be produced by any of the processes described in the above-cited Navia, Neiditch et al., and Walkup et al. patent applications. An understanding of these three processes is useful in order to appreciate the nature of the reaction mixture employed in the process of this invention. Accordingly, these three processes are described in some detail following the Examples that illustrate the process of this invention.
  • the process of this invention employs as a starting mixture the product of a process wherein a sucrose-tin adduct is selectively acylated with an appropriate acylating agent (e.g., an acid anhydride), in a polar aprotic medium such as N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N-methylpyrrolidinone (NMP), N,N-dimethylacetamide (DMA), hexamethylphosphoramide (HMPA), and other polar, aprotic solvents in which sucrose is soluble (the preferred polar aprotic solvent is DMF), to generate a sucrose-6-ester and an acylated form of the tin reagent which possesses substantial solubility in common organic solvents.
  • an appropriate acylating agent e.g., an acid anhydride
  • a polar aprotic medium such as N,N-dimethylformamide (DMF), dimethyl sulfox
  • the effectiveness of this extraction is significantly and substantially augmented by the addition of a small amount of water to the reaction medium prior to extraction.
  • the extractive tin removal is extraordinarily efficient (>99% extractable organotin removal under optimal conditions with as few as two batch extractions).
  • the raffinate (i.e., the liquid remaining after the tin compound has been extracted) resulting from the extractive tin removal contains the polar aprotic solvent, acylated sucrose derivatives (predominantly the S-6-E), residual water, and residual extractant resulting from cross-solubility.
  • the invention provides an extractive technique to preferentially and efficiently separate the organotin byproduct resulting from the tin-mediated 6-acylation reactions of sucrose from the acylated carbohydrate derivatives, thereby permitting the crude in situ carbohydrate product of this reaction to be utilized directly in a subsequent chlorination step without resorting to isolation of the intermediate S-6-E.
  • the fact that the separation can be affected with only small amounts of water being added is an important feature of the invention, since the water must be removed from the sucrose-6-ester solution prior to further processing to produce sucralose, and the cost of the removal of this water is proportional to the amount of it present.
  • the DSDE resulting from the separation process of the invention can be recycled into the sucralose reaction sequence by removal of the extraction solvent and either treatment with an equivalent amount of an alkoxide to generate a reactive distannoxane dialkoxide (for reuse in the process of Navia), or reaction with a slight excess of aqueous caustic to regenerate a di(hydrocarbyl)tin oxide (for reuse in any of the three sucrose-6-ester production processes cited above).
  • sucrose-6-ester (as prepared by the processes cited above) can be realized; e.g., 90-93% yield for sucrose-6-benzoate (“S-6-B”) and 88-91% yield for sucrose-6-acetate (“S-6-A”) by this method, as opposed to yields of approximately 80% for solid S-6-B and 65% for solid S-6-A when crystallization is employed for product isolation.
  • S-6-B sucrose-6-benzoate
  • S-6-A sucrose-6-acetate
  • Added benefits include a reduction in the number of solvents employed (e.g., for crystallization wherein acetone or methanol are used), elimination of the need to recycle crystallization mother liquors, elimination of the need to evaporate a polar aprotic solvent such as DMF, and a reduction in the overall number of equipment items required in the process (e.g., isolation and drying equipment for the S-6-E).
  • solvents employed e.g., for crystallization wherein acetone or methanol are used
  • elimination of the need to recycle crystallization mother liquors elimination of the need to evaporate a polar aprotic solvent such as DMF
  • a polar aprotic solvent such as DMF
  • Solvents useful in carrying out the extractive removal of the DSDE include aliphatic and aromatic hydrocarbons, ethers, chlorinated hydrocarbons, ketones, and esters which show low cross-solubility with water. (By "low cross-solubility with water” is meant that the extraction solvent dissolves less than about one weight per cent water, and water dissolves less than about one weight per cent of the extraction solvent, both solubilities being determined at temperatures below about 20° C.) Though these solvents are often miscible with DMF or other polar aprotic solvents, the presence of the sucrose-6-ester promotes the separation of the extraction mixture into two phases, while the addition of a small amount of water causes efficient DSDE partitioning, thereby allowing the extraction to proceed.
  • Solvents which may be used include hexane, cyclohexane, heptane, and other aliphatic hydrocarbons; benzene, toluene, xylenes, cumene, and other aromatic hydrocarbons; diethyl, methyl t-butyl, diisopropyl, and other ethers; dichloromethane, chloroform, carbon tetrachloride, di-, tri-, and tetrachlorinated ethanes, polychlorinated aliphatic and aromatic hydrocarbons, chlorobenzene, and other chlorinated hydrocarbons; methyl isobutyl ketone and other water immiscible ketones; and water immiscible ester such as methyl benzoate, isopropyl acetate, and ethyl valerate.
  • the preferred solvents are the least polar; the aliphatic hydrocarbons are preferred as they exhibit lower cross solubility with DMF.
  • a boiling point at atmospheric pressure in the range 60°-100° C. is preferred; most preferred are solvents boiling at about 75°-85° C. at atmospheric pressure.
  • the extraction solvent is used in an amount sufficient to effectively extract the DSDE present, e.g., in an amount of at least about 1 ml of extraction solvent per gram of DSDE, preferably at least about 1.5 ml of extraction solvent per gram of DSDE, and more preferably at least about 2 ml of extraction solvent per gram of DSDE present in the extraction mixture.
  • the foregoing proportions are appropriate for the first extraction step.
  • the amount of water used to facilitate the partitioning is dependent in part on the nature of the extraction solvent employed, increased solvent polarity requiring increased amounts of water. Since a preferred aim in carrying out the extraction is to produce a solution of sucrose-6-ester in a solvent such as DMF, which solution is suitable for direct chlorination by the method disclosed in U.S. patent application Ser. No. 382,147 wherein the solution should be anhydrous, it is important for economic reasons to minimize the amount of water employed.
  • the table below shows data on the extraction of the tin compound distannoxane diacetate (“DSDA”) from a 100 g sucrose input scale sucrose-6-acetate reaction mixture (produced by the method of Example 8, first 2 paragraphs), using variable amounts of cyclohexane and water. A single extraction step was used. In commercial practice, it is probable that more than one (e.g., two or three) extraction steps would be used.
  • the total extraction feed (i.e., the DMF solution of S-6-A plus DSDA, not including the cyclohexane) comprised 540 g of solution which contained about 92.6 grams (0.154 mol) of DSDA.
  • the preferred extraction solvents and water quantities employed in the practice of the invention are hydrocarbon solvents and from about three moles of water to about twenty moles of water per mole of DSDE present in the extraction mixture.
  • the preferred extraction solvents are hexane, cyclohexane, and heptane, and the preferred proportions of water are from about five to about ten moles of water per mole of DSDE.
  • a crude reaction mixture of sucrose-6-benzoate and DSDB was prepared (volume about 170 ml), and treated with 100 ml of cumene (isopropyl benzene) and 10 ml (556 mmol, 12.5 equiv basis DSDB) of water.
  • the cloudy biphasic system was mixed thoroughly and allowed to stand to produce two clear liquid phases. They were separated, and the raffinate extracted with additional cumene (3 ⁇ 100 ml). The raffinate was concentrated at 50° C.
  • Table 1 summarizes the results of a series of experiments preparing sucrose-6-benzoate using extractively recovered DSDB.
  • the method was analogous to that recorded in Example 1, on a two-fold larger scale.
  • the initial DSDB charge was prepared by the method of Example 6A, using benzoic anhydride, and isolating by crystallization from 5% aqueous acetonitrile, and the remaining DSDB charges were prepared by using recycled DSDB from the previous cycle.
  • Tin reagent recoveries over 6 cycles averaged 97.7%, the deficit being caused by losses to the potassium benzoate filter cake and by mechanical losses.
  • This Example is an illustration of the aspect of the invention wherein the distannoxane diester extraction product is first reacted with alcoholic alkali to produce a 1,3-di(hydrocarbyloxy)-1,1,3,3-tetra(hydrocarbyl)distannoxane, which is then used in the process of Navia to produce a 1,3-di-(6-O-sucrose)-1,1,3,3-tetra(hydrocarbyl)distannoxane, which is then reacted with an acylating agent to generate a sucrose-6-ester and distannoxane diester. This process may then be repeated in commercial practice.
  • the 1,3-di(hydrocarbyloxy)-1,1,3,3-tetra(hydrocarbyl)distannoxane produced is a 1,3-dialkoxy-1,1,3,3-tetra(alkyl)distannoxane, specifically, 1,3-dibutoxy-1,1,3,3-tetrabutyldistannoxane.
  • DBTO Dibutyltin oxide
  • acetic or benzoic acids (24.1 or 49.1 g, 0.40 mol) in toluene or cyclohexane (200 ml) and the water of reaction was separated in a Dean-Stark trap. Water removal took about 2 hours.
  • the DSDE could be used in solution, or crystallized and isolated by solvent removal and dissolution in either 200 ml of 5% aqueous acetonitrile (DSDB) or 100 ml of 5% aqueous DMF (DSDA).
  • DSDB 5% aqueous acetonitrile
  • DSDA 5% aqueous DMF
  • DBTO (100 g, 0.40 mol) was slurried in cyclohexane (200 ml) at 60° C. and acetic or benzoic anhydrides (20.4 or 45.2 g, 0.20 mol) was added. Stirring was continued for 2 hr at 60° C. by which time the DBTO had completely dissolved.
  • the DSDE was either used in solution or isolated by the methods outlined in Method A to give products in the same yield and exhibiting the same properties as given above.
  • DBTO (114 g, 460 mmol) was refluxed for 2 hr in n-butanol (220 ml) and cyclohexane (50 ml) while 4.0 ml of water were collected in a Dean-Stark trap. A total of 230 ml of mixed solvents were then removed by vacuum distillation to afford a pale-brown slightly turbid oil which consisted of DBDS dissolved in n-butanol.
  • Acetic anhydride (49.2 g, 482 mmol) was added dropwise at a rate sufficient to keep the temperature at 10°-20° C. using external cooling to control the exotherm. The addition took 40 min.
  • the solution was stirred at 20°-25° C. for an additional 0.5 hr, then extracted with cyclohexane (3 ⁇ 250 ml), adding water (15 ml, 833 mmol, 3.62 equiv basis DSDA) to each of the first 2 extractions.
  • the combined extracts (containing the DSDA) were stored for recycle, while the raffinate was concentrated in vacuo to 30% of the original weight to remove water, then diluted with DMF (100 ml) and stored for chlorination to sucralose-6-acetate.
  • the solution (288 g) contained 98.2 g (256 mmol, 58.4% yield) of sucrose-6-acetate by HPLC assay. Atomic absorption spectrophotometry determined the solution contained 0.07% tin, equivalent to 0.4 g DBTO.
  • the resulting clear-brown moisture-sensitive solution which contained DBSS in a mixture of DMF and cyclohexane, was cooled to 0° C. and treated dropwise with 32.8 g (0.321 mol) of acetic anhydride while maintaining the temperature below 10° C. with ice-bath cooling. The mixture was then allowed to warm to 20°-25° C. and stir for 1 hour.
  • the DMF-based raffinate (containing S-6-A, water, and entrained cyclohexane) was then fractionally distilled at 50 mm of Hg and 70° C. (maximum) to remove the water and cyclohexane prior to HPLC analysis (96.1 g, 0.250 mol, 85.7% yield of S-6-A).
  • the cyclohexane extracts (containing DSDA) were combined and concentrated to an oil which was added hot (over 70° C.) in a thin stream over 5 min to a very vigorously agitated solution of 1.1 N aqueous sodium hydroxide (300 ml) at 95° C. Granules of DBTO were rapidly formed. The DBTO slurry was agitated vigorously at 90°-95° C. for 10-15 minutes, then cooled to 30° C. and filtered. The DBTO cake was thoroughly washed with water (3 ⁇ 100 ml) and dried (25-33% loss on drying).
  • the recovered DBTO was used to produce S-6-A by the procedure described above in this Example 8, with the DSDA being extracted, recovered as DBTO, and then again recycled to produce S-6-A by the process of Neiditch et al.
  • Dibutyltin oxide recoveries (corrected for purity), yields of sucrose-6-acetate, and DBTO input composition data for the replicate experiments are presented below in Table 2. (Note that the DBTO was isolated as a hemihydrate.)
  • the preceding example is an illustration of that aspect of the invention wherein the recovered DSDE is treated with aqueous alkali and recovered as a di(hydrocarbyl)tin oxide (in this case, a dialkyltin oxide, and more specifically, dibutyltin oxide), which was then recycled to produce a sucrose-6-ester by the process of Neiditch et al.
  • Said recovered tin oxide could also be employed for reuse in the process of Navia or the process of Walkup et al.
  • This Example illustrates the direct chlorination of the raffinate produced after DSDB extraction (in accordance with the practice of this invention) as an intermediate step in a process for preparing the high-intensity nonnutritive sweetener sucralose.
  • sucrose-6-benzoate (10.0 g, 22.4 mmol) syrup, prepared as described in Example 1 dissolved in 90 ml of dry DMF.
  • sucrose-6-benzoate (10.0 g, 22.4 mmol) syrup
  • argon blanket a 500-ml, 4-neck, round-bottom flask, equipped with mechanical stirring, thermometer, condenser, argon blanket, and addition funnel.
  • sucrose-6-benzoate (10.0 g, 22.4 mmol) syrup
  • argon blanket argon blanket
  • addition funnel To the resulting clear pale-yellow solution, cooled to -38° C., was added dropwise a total of 35.3 ml of phosgene (491 mmol) dissolved in 24 ml of toluene.
  • the addition was exothermic with the internal temperature rising from -38° C. to +14° C. over the course of the addition.
  • the resulting slurry was warmed to 65° C., and the clear solution thus produced heated at 82°-83° C. for 1 and then at 112°-113° C. for 3 hours.
  • the reaction mixture was cooled to 8° C. and treated with enough precooled ( ⁇ 5° C.) 4.0 N NaOH to raise the pH to 9-10 (116 ml). This addition was very exothermic with the temperature rising from 8° C. to 51° C.
  • the mixture was stirred at pH 9-10 for 3 min, and then neutralized by the dropwise addition of acetic acid.
  • the mixture was extracted with ethyl acetate (4 ⁇ 200 ml), and the combined extracts washed with 150 ml of water and decolorized at 45° C. with 4 g of charcoal.
  • the yellow filtrate was concentrated in vacuo at 50° C. to a residual orange syrup which was treated with 50 ml of water and 50 ml of MTBE, and warmed to 50° C.
  • the biphasic mixture was seeded, agitated thoroughly, and cooled to ambient temperature whereupon sucralose-6-benzoate crystallized.
  • the solid was collected by suction filtration, washed twice with a total of 50 ml of MTBE, and dried in vacuo at 50° C. to yield 6.17 g of an off-white solid.
  • sucrose-6-acetate syrup 39.5 g, 103 mmol, prepared and freed from DSDA as described in Example 8) and 272 g of DMF.
  • the resulting solution was vacuum distilled (3-5 Torr) at 35° C. to remove adventitious moisture and residual volatiles. A total of about 70.5 g of distillate was collected.
  • the reaction mixture was neutralized by the addition of a weak-acid ion-exchange resin (acid form).
  • the solution was filtered and the resin washed with methanol (2 ⁇ 250 ml).
  • the combined filtrates were evaporated to a soft foam (245 g) which was dissolved in 1000 ml of water and extracted with ethyl acetate (3 ⁇ 250 ml) to remove methyl benzoate, unreacted sucralose-6-benzoate, and other nonpolar impurities.
  • the aqueous layer was concentrated to a viscous light-brown solution (487 g, 29.0 wt % sucralose, 94.0% crude yield) which was decolorized with charcoal.
  • the solution was concentrated in vacuo to 181 g at 70° C., and crystallization completed by allowing the solution to first cool gradually to 40° C. over 3.5-4.0 hr, followed by cooling at 10° C. for 1.5 hr.
  • Product was recovered by vacuum filtration and dried at 45°-50° C. in vacuo to give 112 g (282 mmol, 74.5% yield) of sucralose [mp 119°-120° C., decomp; [ ⁇ ]20°/D +87.1° (C, 1.23, H 2 O)].
  • the colorless crystalline product had an HPLC purity of 99.6 wt %.
  • the process of Navia comprises the reaction of a 1,3-di(hydrocarbyloxy)-1,1,3,3-tetra(hydrocarbyl)distannoxane [which will be referred to for brevity as a "di(hydrocarbyloxy)-distannoxane”] with sucrose to form a 1,3-di-(6-O-sucrose)-1,1,3,3-tetra(hydrocarbyl)distannoxane [which will be referred to for brevity as a "di(hydrocarbyl)stannoxylsucrose”], which is then reacted with an acylating agent to form a sucrose-6-ester.
  • a byproduct of this reaction is a 1,3-diacyloxy-1,1,3,3-tetra(hydrocarbyl)distannoxane or distannoxane diester.
  • the two reactions are illustrated with the following generalized experimental procedure in which DBTO is used to generate the di(hydrocarbyloxy)distannoxane in situ, and benzoic anhydride is used as the acylating agent:
  • sucrose and di(hydrocarbyloxy)distannoxane reactants are employed in proportions so as to produce the desired 1,3-di-(6-O-sucrose)-1,1,3,3-tetra(hydrocarbyl)distannoxane.
  • the di(hydrocarbyloxy)distannoxane is generated in situ by the reaction of a di(hydrocarbyl)tin oxide ("DHTO") with a lower alkanol such as methanol
  • DHTO di(hydrocarbyl)tin oxide
  • sucrose are preferably employed in stoichiometric ratios of about one-to-one.
  • hydrocarbyl groups bonded to tin can be, individually, alkyl, cycloalkyl, aryl, or arylalkyl such as, for example, methyl, ethyl, propyl, butyl, octyl, benzyl, phenethyl, phenyl, naphthyl, cyclohexyl, and substituted phenyl.
  • the preferred hydrocarbyl groups are alkyl having up to eight carbon atoms.
  • a di(hydrocarbyl)tin dialkoxide, dihalide, diacylate, or other organic tin compound can be used as long as it generates the di(hydrocarbyloxy)distannoxane in situ.
  • the reaction is carried out in an organic liquid reaction medium that is a solvent for suorose and the di(hydrocarbyloxy)-distannoxane.
  • the reaction medium is preferably also a solvent for the compound(s) that are used to generate the di(hydrocarbyloxy)distannoxane. More preferably, the reaction medium is also one of the reactants that are used to generate the di(hydrocarbyloxy)distannoxane in situ.
  • a wide variety of aliphatic and cycloaliphatic alcohols or phenols can be used as the reaction medium.
  • the preferred reaction mediums are primary lower alkanols such as methanol, ethanol, n-propanol, n-butanol, n-pentanol, and n-hexanol.
  • Additional alcohols and phenols that may be used as the reactant/reaction medium include phenol, substituted phenols such as lower alkyl-substituted phenols, cyclohexanol and substituted cyclohexanols such as lower alkyl-substituted cyclohexanols.
  • Inert organic liquids such as toluene, xylene, and other hydrocarbons may be used as diluents in the reaction, if desired.
  • the reaction between sucrose and the di(hydrocarbyloxy)distannoxane is carried out at a temperature and for a period of time sufficient to form a di(hydrocarbyl)stannoxylsucrose.
  • Illustrative reaction temperatures are within the range of from about 50° C. to about 100° C.
  • Illustrative reaction times are from about 1 to about 24 hours.
  • the di(hydrocarbyl)stannoxylsucrose is recovered by evaporating the reaction medium, which may be performed under reduced pressure if desired.
  • the di(hydrocarbyl)stannoxylsucrose product of the evaporation is used directly without further purification in the acylation reaction.
  • acylating agents that can be used are the various anhydrides of benzoic and substituted benzoic acid (e.g., 4-nitrobenzoic acid, 3,5-dinitro-benzoic acid, and the like), alkanoic acids such as acetic acid, propionic acid, butyric acid, cyclohexanecarboxylic acid, long chain fatty acids, both saturated and unsaturated, such as stearic acid, oleic acid, linoleic acid, and the like, having up to, for example, 28 carbon atoms, unsaturated acids such as acrylic acid and methacrylic acid, substituted acids such chloroacetic acid, cyanoacetic acid, phenoxyacetic acid, and the like, and saturated and unsaturated dicarboxylic acids such as phthalic acid, maleic acid, glutaric acid, and the like.
  • alkanoic acids such as acetic acid, propionic acid, butyric acid, cyclohexanecarboxylic acid, long
  • the acylation reaction is carried out in an inert organic reaction vehicle such as DMF or other polar aprotic solvents such as DMSO, NMP, DMF, HMPA, and other polar aprotic solvents in which sucrose is soluble.
  • DMF is the preferred polar aprotic solvent because of its low cost, its relatively low boiling point, and its suitability as a solvent for further steps in the process for producing sucralose.
  • the acylation reaction is carried out at a temperature and for a period of time sufficient to prepare the S-6-E product.
  • the anhydride is a liquid, it may be added neat to the sucrose-organotin adduct, or it may be diluted with an inert cosolvent. If the anhydride is a solid, it may be added in the solid form or added as a solution in an appropriate inert solvent. The anhydride may be added all at once, or it may be added slowly over a period of time.
  • Anhydride stoichiometry is an important aspect of the successful practice of this invention.
  • the use of too little anhydride will result in a S-6-E product contaminated by residual sucrose.
  • the use of too much anhydride will cause sucrose diester contamination.
  • the most preferred stoichiometric ratio uses the anhydride in a slight (5-10%) molar excess (basis sucrose) in order to insure the near absence of sucrose in the product.
  • Acylation temperatures from below 0° C. to about 30° C. have been employed experimentally.
  • the upper limit of acceptable acylation temperatures is governed by the onset of thermally activated nonregioselective acylation reactions which will result in the formation of undesirable sucrose mono- and diesters. From a practical standpoint, this temperature limit is a function of the reactivity of the acid anhydride. For example, because acetic anhydride is a relatively reactive species, acylations with it are normally carried out below about 20° C. Benzoic anhydride, on the other hand, being somewhat less reactive, allows for acylation at room temperature or slightly above.
  • acylation reactions are mildly exothermic. Depending upon initial reaction temperature and rate of anhydride addition to the di(hydrocarbyl)tin-sucrose adduct, external cooling of the acylation process might be required in order that thermally activated nonregioselective acylation be minimized.
  • the times required for the acylations of the sucrose adducts to go to completion are dependent upon the concentration of the reactants (as the acylation is a multiple-order process), the reactivity of the acylating agent, and the temperature of the reaction mixture. Although times of from one hour to several days have been employed in the laboratory, there is no advantage to extending the reaction period longer than that time necessary for consumption of the acylating agent. This is generally complete within from about one to about five hours under typical conditions.
  • the process is carried out by reacting sucrose with a di(hydrocarbyl)tin oxide in an inert organic vehicle.
  • DHTO's that can be used are those described above with respect to the process of Navia.
  • the DHTO and sucrose may be employed in a wide range of stoichiometric ratios. However, stoichiometric ratios of about one-to-one are preferred. This is because the use of an excess of sucrose leads to contamination of the S-6-E by sucrose and undesired sucrose esters, while the use of excess DHTO causes contamination of the S-6-E product by sucrose diesters.
  • the most preferred stoichiometric ratio uses the DHTO in a very slight (1-3%) molar excess (basis sucrose) in order to insure the near absence of sucrose in the product.
  • the process of Neiditch et al. is carried out in an inert organic reaction vehicle.
  • inert is meant that the reaction vehicle is free of any organic functional groups that will react with either the sucrose or the DHTO.
  • the inert organic reaction vehicle will be a mixed solvent system comprising a polar aprotic solvent and a cosolvent.
  • the polar aprotic solvent is employed for the purpose of dissolving the sucrose
  • the cosolvent is employed for the purpose of codistillatively removing all water generated by the reaction of sucrose with the DHTO and also promoting the solubility of the DHTO.
  • the polar aprotic solvents which can be employed include are those that were described above with respect to the process of Navia. DMF is the preferred polar aprotic solvent.
  • Cosolvents capable of codistillatively removing the water of condensation include chlorinated hydrocarbons such as chloroform, a variety of saturated and aromatic hydrocarbons such as hexane, heptane, octane, cyclohexane, benzene, and toluene, ketones such as methyl ethyl ketone and methyl isobutyl ketone, acyclic and cyclic eithers such as tetrahydrofuran, and other inert organic liquids that meet the criteria set forth herein.
  • chlorinated hydrocarbons such as chloroform
  • saturated and aromatic hydrocarbons such as hexane, heptane, octane, cyclohexane, benzene, and toluene
  • ketones such as methyl ethyl ketone and methyl isobutyl ketone
  • acyclic and cyclic eithers such as tetrahydrofur
  • the primary criteria for a cosolvent are (1) that is produce a mixture with the polar aprotic solvent, the DHTO, and the sucrose, which refluxes at atmospheric pressure with an internal reaction temperature within the range of from about 75° C. to about 125° C., (2) that it codistill the water produced by the condensation of the DHTO and sucrose, thereby facilitating removal of water during the reaction, and (3) that it promote the solubility of the DHTO in the reaction mixture (since DHTO's are usually not soluble to any significant degree in polar aprotic solvents) and thereby enhance the rate of reaction of the DHTO with sucrose.
  • Cosolvents which are immiscible with water and which do form a constant-composition minimum-boiling azeotrope with water are preferred, but, as has been determined by experimentation, reaction systems employing such cosolvents typically reflux at temperatures significantly higher than either the water-azeotrope boiling point or the boiling point of the pure solvent. There is also data showing that the water-cosolvent compositions of the distillates arising from these systems are not constant throughout the DHTO-sucrose condensation period.
  • Preferred cosolvents for reasons of chemical stability, efficiency of water removal, cost, and boiling point include cyclohexane, n-heptane, and isooctane (2,2,4-trimethylpentane).
  • the reaction between sucrose and the DHTO is carried out at a temperature within the range of from about 75° C. to about 125° C. Below 75° C., the reaction becomes uneconomically slow, and above 125° C. there is a tendency for the carbohydrate to decompose.
  • the preferred reaction temperature is within the range of about 80° C. to about 100° C., and more preferably, from about 85° C. to about 90° C.
  • the product of the reaction of sucrose and DHTO is a di(hydrocarbyl)stannoxylsucrose, the same product as in the Navia process. This product is acylated as in the Navia process, with the same product mixture being produced (i.e., a sucrose-6-ester and a DSDE byproduct).
  • Walkup et al. The process of Walkup et al. is outlined as follows:
  • the first step in the process comprises the reaction of a DHTO with a dihydric alcohol, an alkanolamine, or an enolizable ⁇ -hydroxy ketone in an inert organic vehicle such as a normally liquid hydrocarbon, with removal of water, at a temperature and for a period of time sufficient to produce a cyclic adduct of said dihydric alcohol, alkanolamine, or ⁇ -hydroxy ketone.
  • an inert organic vehicle employed is preferably one that is capable of removing water by azeotropic distillation. Hydrocarbons having boiling points between about 80° C. and 145° C. are preferred. Specific illustrative examples of such inert organic vehicles are cyclohexane, benzene, toluene, any of the xylenes, or mixtures thereof.
  • the di(hydrocarbyl)tin oxides employed in the Walkup et al. process are the same as those disclosed above with respect to the Navia process.
  • the DHTO is reacted with a dihydric alcohol, an alkanolamine, or an ⁇ -hydroxy ketone.
  • dihydric alcohols include alkane diols such as ethylene glycol, 2,3-propanediol, 2,3-butanediol, 1,3-butanediol, 1,4-butanediol, 1,3-propanediol, 1,2-pentanediol, 1,2-hexanediol, and other alkane diols that contain, for example, up to about eight carbon atoms, and cycloalkane diols such as 1,2-cyclohexanediol, 1,2-cyclopentanediol, and the like.
  • alkane diols such as ethylene glycol, 2,3-propanediol, 2,3-butanediol, 1,3-butanediol, 1,4-butanediol, 1,3-propanediol, 1,2-pentanediol, 1,2-hexanedio
  • the hydroxyl groups on the dihydric alcohol are not more than four carbon atoms distant from each other on the carbon chain to which they are bonded.
  • alkanolamines that can be used include ethanolamine, 2-amino-1-propanol, and 1-amino-2-propanol.
  • the amino and hydroxyl groups on the alkanolamine are not more than four carbon atoms distant from each other on the carbon chain to which they are bonded.
  • Specific illustrative examples of ⁇ -hydroxy ketones that are capable of enolization to enediols include benzoin (2-hydroxy-2-phenylacetophenone) and acetoin (3-hydroxy-2-butanone).
  • the preferred compounds for use in reacting with the DHTO are the alkane diols, particularly, ethylene glycol, since it gives excellent yields and is itself inexpensive.
  • the DHTO which is normally insoluble in the inert organic reaction vehicle employed, may be suspended in the vehicle.
  • the diol, alkanolamine, or ⁇ -hydroxy ketone (in slight stoichiometric excess) to be employed for the adduct formation is then added and the mixture is heated to reflux, which is normally at a temperature of from about 80° C. to about 145° C.
  • Water is removed azeotropically as it formed as a result of the condensation between the di(hydrocarbyl)tin oxide and the diol, alkanolamine, or ⁇ -hydroxy ketone to afford homogeneous colorless solutions of the cyclic adducts. Reaction times of from about two to about four hours are typical for this step.
  • These intermediates may then be isolated by concentration and crystallization. It is usually more convenient to evaporate the solvent to produce a solid or a semisolid di(hydrocarbyl)tin adduct, which is then dispersed in DMF or another solvent in which sucrose has an appropriate degree of solubility, which is used as the reaction medium for Step (b) of the process of the invention.
  • solvents include DMF, DMSO, DMA, and the like, and other polar aprotic solvents in which sucrose is soluble, as discussed above.
  • Step (b) sucrose is added to the reaction mixture which comprises the adduct product of Step (a) and the inert organic reaction vehicle such as DMF.
  • the resulting suspension is stirred at ambient temperature for a period of time sufficient to form the 6-O-[dihydrocarbyl(hydroxy- or amino- or oxohydrocarbyl)stannoxyl]sucrose intermediate, which usually takes from about twelve to about twenty-four hours.
  • heating e.g., up to about 85° C. may be applied to increase the sucrose dissolution rate and shorten reaction time to about sixty minutes.
  • Step (c) the usually turbid mixtures, which contain the reactive 6-O-[dihydrocarbyl(hydroxy- or amino- or oxohydrocarbyl)stannoxyl]sucrose intermediate and which comprise the product of Step (b), are then treated with two molar equivalents of an acylating agent such as a carboxylic acid anhydride at ambient temperature.
  • an acylating agent such as a carboxylic acid anhydride
  • the mixtures are quenched by the addition of water or methanol, filtered if necessary to remove any extraneous solids, extracted if desired to remove di(hydrocarbyl)tin byproducts, concentrated to a residual gum or oil with mild heating under reduced pressure, and then further processed and assayed as necessary (function of acyl group) prior to further processing, such as chlorination when the S-6-E is to be used in the production of sucralose.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Biochemistry (AREA)
  • Biotechnology (AREA)
  • General Health & Medical Sciences (AREA)
  • Genetics & Genomics (AREA)
  • Molecular Biology (AREA)
  • Saccharide Compounds (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Catalysts (AREA)
US07/512,690 1990-04-23 1990-04-23 Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds Expired - Lifetime US5034551A (en)

Priority Applications (23)

Application Number Priority Date Filing Date Title
US07/512,690 US5034551A (en) 1990-04-23 1990-04-23 Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds
GR910100149A GR1002083B (en) 1990-04-23 1991-04-09 Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds
NZ237765A NZ237765A (en) 1990-04-23 1991-04-09 Extraction of 1,3-diacyloxy-1,1,3,3-tetra(hydroxycarbyl)distannoxanes from a mixture with sucrose-6-esters by adding water to partition the compounds between two phases; preparation of di(hydrocarbyl)tin oxides
PH42296A PH27407A (en) 1990-04-23 1991-04-16 Process for recovery or organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds
IL9789191A IL97891A (en) 1990-04-23 1991-04-17 Sabbath Organo-tin esters from mixtures containing them
AU75377/91A AU631062B2 (en) 1990-04-23 1991-04-19 Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds
JP3113708A JP2882548B2 (ja) 1990-04-23 1991-04-19 有機錫エステルを含む反応混合物から同化合物の回収法及び回収した有機錫化合物の再使用
YU71591A YU48759B (en) 1990-04-23 1991-04-20 Process for delivery of organotin esters from reaction mixtures containig the same
ES91303565T ES2080895T3 (es) 1990-04-23 1991-04-22 Procedimiento para la recuperacion de esteres de organoestaño a partir de mezclas de reaccion que los contienen y reutilizacion de estos compuestos de organoestaño recuperados.
ZA912995A ZA912995B (en) 1990-04-23 1991-04-22 Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds
DE69113106T DE69113106T2 (de) 1990-04-23 1991-04-22 Verfahren zur Wiedergewinnung von Organozinnestern aus diese enthaltenden Reaktionsgemischen und Wiederverwendung der wiedergewonnenen Organozinnverbindungen.
NO911590A NO180009C (no) 1990-04-23 1991-04-22 Fremgangsmåter for isolering av organotinnestere fra reaksjonsblandinger som inneholder disse og gjenanvendelse av isolerte organotinnforbindelser.
SU914895127A RU2036197C1 (ru) 1990-04-23 1991-04-22 Способ экстракции 1,3-диацилокси-1,1,3,3-тетра(гидрокарбил)дистанноксана из смеси
DK91303565.5T DK0455390T3 (da) 1990-04-23 1991-04-22 Fremgangsmåde til afgivelse af organotinestere fra reaktionsblandinger indeholdende de samme og genanvendelse af de genvundne organotinforbindelser
TR41091A TR25514A (tr) 1990-04-23 1991-04-22 Organo kalay esterleri ihtiva eden reaksiyon karisimlarindan bunlari geri kazanmaya mahsus yöntem ve geri kazanilmis organo kalay bilesiklerinin tekrar kullanimi
FI911941A FI97886C (fi) 1990-04-23 1991-04-22 Orgaanisten tinaestereiden talteenottomenetelmä reaktioseoksista, jotka sisältävät niitä, ja talteenotettujen orgaanisten tinayhdisteiden uudelleenkäyttö
IE134391A IE68437B1 (en) 1990-04-23 1991-04-22 Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds
CA002040933A CA2040933C (en) 1990-04-23 1991-04-22 Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds
KR1019910006388A KR0176972B1 (ko) 1990-04-23 1991-04-22 유기 주석 에스테르를 함유하는 반응 혼합물로부터 그를 회수하는 방법 및 회수된 유기 주석 화합물의 재사용
PT97432A PT97432B (pt) 1990-04-23 1991-04-22 Processo para a preparacao de esteres de organo-estanho por recolha dos mesmos em misturas de reaccao que os contem
EP91303565A EP0455390B1 (en) 1990-04-23 1991-04-22 Process for delivery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds
MX25476A MX165090B (es) 1990-04-23 1991-04-23 Procedimiento para recuperar esteres de organoestaño a partir de mezclas de reaccion que los contienen y reutilizar los compuestos de organoestaño recuperados.
TW080106687A TW197443B (es) 1990-04-23 1991-08-23

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US07/512,690 US5034551A (en) 1990-04-23 1990-04-23 Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds

Publications (1)

Publication Number Publication Date
US5034551A true US5034551A (en) 1991-07-23

Family

ID=24040135

Family Applications (1)

Application Number Title Priority Date Filing Date
US07/512,690 Expired - Lifetime US5034551A (en) 1990-04-23 1990-04-23 Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds

Country Status (23)

Country Link
US (1) US5034551A (es)
EP (1) EP0455390B1 (es)
JP (1) JP2882548B2 (es)
KR (1) KR0176972B1 (es)
AU (1) AU631062B2 (es)
CA (1) CA2040933C (es)
DE (1) DE69113106T2 (es)
DK (1) DK0455390T3 (es)
ES (1) ES2080895T3 (es)
FI (1) FI97886C (es)
GR (1) GR1002083B (es)
IE (1) IE68437B1 (es)
IL (1) IL97891A (es)
MX (1) MX165090B (es)
NO (1) NO180009C (es)
NZ (1) NZ237765A (es)
PH (1) PH27407A (es)
PT (1) PT97432B (es)
RU (1) RU2036197C1 (es)
TR (1) TR25514A (es)
TW (1) TW197443B (es)
YU (1) YU48759B (es)
ZA (1) ZA912995B (es)

Cited By (50)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5498709A (en) * 1994-10-17 1996-03-12 Mcneil-Ppc, Inc. Production of sucralose without intermediate isolation of crystalline sucralose-6-ester
US5545600A (en) * 1994-12-21 1996-08-13 Knudsen; George A. Process for the preparation of dialkyltin dialkoxide
GB2275923B (en) * 1993-03-12 1996-12-04 Mcneil Ppc Inc Sucralose pentaester production
EP0776903A1 (en) 1995-11-28 1997-06-04 McNEIL-PPC, INC. Improved sucrose-6-ester process
US6087528A (en) * 1997-05-30 2000-07-11 Mitsubishi Chemical Corporation Process for producing hydroxyalkyl monoacrylate using stannoxane catalysts
US6121430A (en) * 1998-12-28 2000-09-19 University Of Iowa Research Foundation Regiospecific synthesis of glucose-based surfactants
US20030190395A1 (en) * 2002-04-05 2003-10-09 Vernon Nicholas M. Methods for buffer stabilized aqueous deacylation
US6998480B2 (en) 2002-03-08 2006-02-14 Tate & Lyle Public Limited Company Process for improving sucralose purity and yield
US20060276639A1 (en) * 2005-06-01 2006-12-07 Healthy Brands, Llc Conversion of sucralose-6-ester to sucralose
US20070160732A1 (en) * 2006-01-10 2007-07-12 Alembic Limited Process for purification of sucralose
US20080227971A1 (en) * 2007-01-19 2008-09-18 Leinhos Duane A Deacylation of sucralose-6-acylates
CN100420695C (zh) * 2007-02-02 2008-09-24 上海迪赛诺医药发展有限公司 制备三氯蔗糖的方法
US20080234472A1 (en) * 2007-01-19 2008-09-25 Duane Leinhos Sucralose production method
EP2039699A2 (en) 2002-03-08 2009-03-25 Tate & Lyle Technology Limited Extractive methods for purifying sucralose
US20090234113A1 (en) * 2008-03-13 2009-09-17 Tate & Lyle Technology Ltd. Microbial consortia and methods for their use
US20090247737A1 (en) * 2008-03-26 2009-10-01 Tate & Lyle Technology Limited Method for the production of sucralose
US20090259034A1 (en) * 2008-03-20 2009-10-15 Tate & Lyle Technology Limited Removal of acids from tertiary amide solvents
US20090259036A1 (en) * 2008-04-03 2009-10-15 Tate & Lyle Technology Limited Extraction of less polar impurities from sucralose containing aqueous feed streams
US20090264633A1 (en) * 2008-01-04 2009-10-22 Tate & Lyle Technology Limited Method for the production of sucralose
US20090281295A1 (en) * 2008-04-03 2009-11-12 Tate & Lyle Technology Limited Crystallization of sucralose from sucralose-containing feed streams
US20090299054A1 (en) * 2008-04-03 2009-12-03 Tate & Lyle Technology Limited Sucralose purification process
US20090299055A1 (en) * 2008-04-03 2009-12-03 Tate & Lyle Technology Limited Purification of Sucralose Containing Feed Streams for Sucralose Crystallization
US20090312538A1 (en) * 2006-07-06 2009-12-17 Alembic Limited process for the preparation of sucralose of high purity
US20100041908A1 (en) * 2006-10-11 2010-02-18 Masaaki Shinohata Process for producing dialkyl tin dialkoxides
US20100056773A1 (en) * 2007-01-08 2010-03-04 V.B. Medicare Pvt. Ltd. Decolorization of process streams by chemical oxidation in the manufacture of trichlorogalactosucrose
US20100081803A1 (en) * 2008-04-03 2010-04-01 Tate & Lyle Technology Limited Effect of carbohydrate concentration on sucralose extraction efficiency
WO2010112813A1 (en) 2009-03-30 2010-10-07 Tate & Lyle Technology Limited Process for removing dimethylamine
WO2010114683A1 (en) 2009-03-31 2010-10-07 Tate & Lyle Technology Ltd Base-assisted formation of tin-socrose adducts
WO2010151489A1 (en) 2009-06-22 2010-12-29 Tate & Lyle Technology Limited Purification of tertiary formamide contaminated with tertiary acetamide
CN101979396A (zh) * 2010-10-13 2011-02-23 南京甘倍加生物科技有限责任公司 蔗糖-6-酯及三氯蔗糖的合成方法
GB2474310A (en) * 2009-10-12 2011-04-13 Tate & Lyle Technology Ltd A process for the production of sucrose-6-ester
GB2474311A (en) * 2009-10-12 2011-04-13 Tate & Lyle Technology Ltd A process for the production of sucrose-6-ester
CN102627675A (zh) * 2012-03-29 2012-08-08 湖北益泰药业有限公司 一种制备蔗糖-6-酯的方法
WO2012153128A1 (en) 2011-05-10 2012-11-15 Tate & Lyle Technology Limited Extraction of carboxylic acids with tin compounds
CN103130843A (zh) * 2013-01-21 2013-06-05 溧阳维信生物科技有限公司 蔗糖制备蔗糖-6-乙酯过程中二丁基氧化锡的回收再利用的方法
CN104098617A (zh) * 2013-04-08 2014-10-15 南京工业大学 一种蔗糖-6-乙酸酯的制备方法
CN104387427A (zh) * 2014-10-30 2015-03-04 安徽金禾实业股份有限公司 一种三氯蔗糖的生产方法
WO2015092374A1 (en) 2013-12-16 2015-06-25 Tate & Lyle Technology Limited Chlorination of sucrose-6-esters
CN105111246A (zh) * 2015-08-22 2015-12-02 安徽金禾实业股份有限公司 三氯蔗糖生产中有机锡的回收方法
WO2016020635A1 (en) 2014-08-08 2016-02-11 Tate & Lyle Technology Limited Chlorination of sucrose-6-esters
CN108558962A (zh) * 2018-05-22 2018-09-21 山东新和成精化科技有限公司 一种用于合成蔗糖-6-酯的方法
US10179760B2 (en) 2015-03-17 2019-01-15 Tate & Lyle Technology Limited DMF distillation
US10370398B2 (en) 2016-06-23 2019-08-06 Tate & Lyle Technology Limited Liquid-liquid extraction of DMF
CN110590832A (zh) * 2019-08-15 2019-12-20 安徽金禾实业股份有限公司 三氯蔗糖生产中回收的有机锡乙酸酯的提纯方法
CN111574572A (zh) * 2020-05-22 2020-08-25 安徽金禾实业股份有限公司 一种三氯蔗糖生产中有机锡催化剂连续性制备补充的方法
CN112125938A (zh) * 2020-09-26 2020-12-25 安徽金禾实业股份有限公司 一种从糖渣萃取三氯蔗糖-6-乙酯的方法
CN112495442A (zh) * 2020-12-02 2021-03-16 安徽金禾实业股份有限公司 一种蔗糖-6-乙酯生产中回收制备有机锡催化剂的方法
CN112771059A (zh) * 2020-12-30 2021-05-07 安徽金禾实业股份有限公司 三氯蔗糖的制备方法、粗产品溶液及三氯蔗糖
CN114133411A (zh) * 2021-11-23 2022-03-04 安徽金禾实业股份有限公司 一种三氯蔗糖中萃取絮状物的方法
CN116217635A (zh) * 2023-03-02 2023-06-06 福建桦智工程技术有限公司 一种蔗糖-6-乙酸酯脱酸提纯的方法

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5023329A (en) * 1990-04-23 1991-06-11 Noramco, Inc. Sucrose-6-ester production process
AU2691802A (en) * 2000-11-17 2002-05-27 Mcneil Ppc Inc Improved sucralose composition and process for its preparation
WO2005090376A1 (en) * 2004-03-19 2005-09-29 Pharmed Medicare Private Limited An improved process for producing chlorinated sucrose
CN109575069A (zh) * 2018-12-10 2019-04-05 安徽金禾实业股份有限公司 一种三氯蔗糖生产中催化剂的回收方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3846459A (en) * 1972-10-18 1974-11-05 Cincinnati Milacron Chem Organotin mercaptocarboxylates
US3962295A (en) * 1972-05-10 1976-06-08 John Desmond Collins Novel diorganotin derivatives of α, ω-dimercaptans and method for preparing same
US4254017A (en) * 1978-11-13 1981-03-03 M&T Chemicals Inc. Organotin mercaptoalkanol esters and alkoxides containing sulfide groups
US4434102A (en) * 1979-07-19 1984-02-28 Witco Chemical Corporation Preparation of mixtures of methyltin trichloride and dimethyltin dichloride from stanic chloride and dimethyltin dichloride without catalyst and conversion to mixed methyltin mercaptide stabilizers
US4711920A (en) * 1986-07-23 1987-12-08 Morton Thiokol, Inc. Stabilizers for halogen-containing polymers comprising the product of a diorganotin oxide, an ethylenically unsaturated dicarboxylic acid ester and a mercaptan
US4950746A (en) * 1988-07-18 1990-08-21 Noramco, Inc. Process for synthesizing sucrose derivatives by regioselective reaction

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4269782A (en) * 1979-07-19 1981-05-26 Argus Chemical Corporation Preparation of mixtures of methyltin trichloride and dimethyltin dichloride from stannic chloride and dimethyltin dichloride
US5089608A (en) * 1990-03-23 1992-02-18 Mcneil-Ppc, Inc. Selective 6-acylation of sucrose mediated by cyclic adducts of dialkyltin oxides and diols

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3962295A (en) * 1972-05-10 1976-06-08 John Desmond Collins Novel diorganotin derivatives of α, ω-dimercaptans and method for preparing same
US3846459A (en) * 1972-10-18 1974-11-05 Cincinnati Milacron Chem Organotin mercaptocarboxylates
US4254017A (en) * 1978-11-13 1981-03-03 M&T Chemicals Inc. Organotin mercaptoalkanol esters and alkoxides containing sulfide groups
US4434102A (en) * 1979-07-19 1984-02-28 Witco Chemical Corporation Preparation of mixtures of methyltin trichloride and dimethyltin dichloride from stanic chloride and dimethyltin dichloride without catalyst and conversion to mixed methyltin mercaptide stabilizers
US4711920A (en) * 1986-07-23 1987-12-08 Morton Thiokol, Inc. Stabilizers for halogen-containing polymers comprising the product of a diorganotin oxide, an ethylenically unsaturated dicarboxylic acid ester and a mercaptan
US4950746A (en) * 1988-07-18 1990-08-21 Noramco, Inc. Process for synthesizing sucrose derivatives by regioselective reaction

Cited By (87)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2275923B (en) * 1993-03-12 1996-12-04 Mcneil Ppc Inc Sucralose pentaester production
EP0708110A2 (en) 1994-10-17 1996-04-24 McNEIL-PPC, INC. Production of sucralose without intermediate isolation of crystalline sucralose-6-ester
US5498709A (en) * 1994-10-17 1996-03-12 Mcneil-Ppc, Inc. Production of sucralose without intermediate isolation of crystalline sucralose-6-ester
US5545600A (en) * 1994-12-21 1996-08-13 Knudsen; George A. Process for the preparation of dialkyltin dialkoxide
EP0776903A1 (en) 1995-11-28 1997-06-04 McNEIL-PPC, INC. Improved sucrose-6-ester process
US6087528A (en) * 1997-05-30 2000-07-11 Mitsubishi Chemical Corporation Process for producing hydroxyalkyl monoacrylate using stannoxane catalysts
US6121430A (en) * 1998-12-28 2000-09-19 University Of Iowa Research Foundation Regiospecific synthesis of glucose-based surfactants
US6998480B2 (en) 2002-03-08 2006-02-14 Tate & Lyle Public Limited Company Process for improving sucralose purity and yield
EP2039699A2 (en) 2002-03-08 2009-03-25 Tate & Lyle Technology Limited Extractive methods for purifying sucralose
US6890581B2 (en) 2002-04-05 2005-05-10 Tate & Lyle Public Limited Company Methods for buffer stabilized aqueous deacylation
US20050170069A1 (en) * 2002-04-05 2005-08-04 Vernon Nicholas M. Methods for buffer stabilized aqueous deacylation
US20030190395A1 (en) * 2002-04-05 2003-10-09 Vernon Nicholas M. Methods for buffer stabilized aqueous deacylation
US20060276639A1 (en) * 2005-06-01 2006-12-07 Healthy Brands, Llc Conversion of sucralose-6-ester to sucralose
US20070160732A1 (en) * 2006-01-10 2007-07-12 Alembic Limited Process for purification of sucralose
US7741477B2 (en) 2006-01-10 2010-06-22 Alembic Limited Process for purification of sucralose
US20090312538A1 (en) * 2006-07-06 2009-12-17 Alembic Limited process for the preparation of sucralose of high purity
US8008518B2 (en) * 2006-10-11 2011-08-30 Asahi Kasei Chemicals Corporation Process for producing dialkyl tin dialkoxides
US20100041908A1 (en) * 2006-10-11 2010-02-18 Masaaki Shinohata Process for producing dialkyl tin dialkoxides
US20100056773A1 (en) * 2007-01-08 2010-03-04 V.B. Medicare Pvt. Ltd. Decolorization of process streams by chemical oxidation in the manufacture of trichlorogalactosucrose
US20080227971A1 (en) * 2007-01-19 2008-09-18 Leinhos Duane A Deacylation of sucralose-6-acylates
US20080234472A1 (en) * 2007-01-19 2008-09-25 Duane Leinhos Sucralose production method
CN100420695C (zh) * 2007-02-02 2008-09-24 上海迪赛诺医药发展有限公司 制备三氯蔗糖的方法
US20090264633A1 (en) * 2008-01-04 2009-10-22 Tate & Lyle Technology Limited Method for the production of sucralose
US8436156B2 (en) 2008-01-04 2013-05-07 Tate & Lyle Technology Limited Method for the production of sucralose
US20090234113A1 (en) * 2008-03-13 2009-09-17 Tate & Lyle Technology Ltd. Microbial consortia and methods for their use
US8557976B2 (en) 2008-03-13 2013-10-15 Tate & Lyle Technology Limited Microbial consortia and methods for their use
US8476424B2 (en) 2008-03-20 2013-07-02 Tate & Lyle Technology Limited Removal of acids from tertiary amide solvents
US20090259034A1 (en) * 2008-03-20 2009-10-15 Tate & Lyle Technology Limited Removal of acids from tertiary amide solvents
US20090247737A1 (en) * 2008-03-26 2009-10-01 Tate & Lyle Technology Limited Method for the production of sucralose
US8436157B2 (en) 2008-03-26 2013-05-07 Tate & Lyle Technology Limited Method for the production of sucralose
US20100081803A1 (en) * 2008-04-03 2010-04-01 Tate & Lyle Technology Limited Effect of carbohydrate concentration on sucralose extraction efficiency
US20090299055A1 (en) * 2008-04-03 2009-12-03 Tate & Lyle Technology Limited Purification of Sucralose Containing Feed Streams for Sucralose Crystallization
US20090299054A1 (en) * 2008-04-03 2009-12-03 Tate & Lyle Technology Limited Sucralose purification process
US8497367B2 (en) 2008-04-03 2013-07-30 Tate & Lyle Technology Limited Sucralose purification process
US20090281295A1 (en) * 2008-04-03 2009-11-12 Tate & Lyle Technology Limited Crystallization of sucralose from sucralose-containing feed streams
US8212022B2 (en) 2008-04-03 2012-07-03 Tate & Lyle Technology Limited Effect of carbohydrate concentration on sucralose extraction efficiency
US20090259036A1 (en) * 2008-04-03 2009-10-15 Tate & Lyle Technology Limited Extraction of less polar impurities from sucralose containing aqueous feed streams
WO2010112813A1 (en) 2009-03-30 2010-10-07 Tate & Lyle Technology Limited Process for removing dimethylamine
US8912320B2 (en) 2009-03-30 2014-12-16 Tate & Lyle Technology Limited Process for removing dimethylamine
CN102365292A (zh) * 2009-03-31 2012-02-29 塔特和莱利技术有限公司 锡-蔗糖加合物的碱辅助形成
CN102365292B (zh) * 2009-03-31 2016-03-30 塔特和莱利技术有限公司 锡-蔗糖加合物的碱辅助形成
US8927706B2 (en) 2009-03-31 2015-01-06 Tate & Lyle Technology, Ltd. Based-assisted formation of tin-sucrose adducts
WO2010114683A1 (en) 2009-03-31 2010-10-07 Tate & Lyle Technology Ltd Base-assisted formation of tin-socrose adducts
WO2010151489A1 (en) 2009-06-22 2010-12-29 Tate & Lyle Technology Limited Purification of tertiary formamide contaminated with tertiary acetamide
US8981079B2 (en) 2009-06-22 2015-03-17 Tate & Lyle Technology Limited Purification of tertiary formamide contaminated with tertiary acetamide
GB2474310A (en) * 2009-10-12 2011-04-13 Tate & Lyle Technology Ltd A process for the production of sucrose-6-ester
CN102639551A (zh) * 2009-10-12 2012-08-15 塔特和莱利技术有限公司 蔗糖-6-酯的生产方法
GB2474310B (en) * 2009-10-12 2012-02-29 Tate & Lyle Technology Ltd Process for the production of sucrose-6-ester
US9073959B2 (en) 2009-10-12 2015-07-07 Tate & Lyle Technology Limited Process for the production of sucrose-6-ester
US20110087018A1 (en) * 2009-10-12 2011-04-14 Tate & Lyle Technology Limited Low Temperature, Single Solvent Process for the Production of Sucrose-6-Ester
GB2474311A (en) * 2009-10-12 2011-04-13 Tate & Lyle Technology Ltd A process for the production of sucrose-6-ester
WO2011045565A1 (en) 2009-10-12 2011-04-21 Tate & Lyle Technology Limited Process for the production of sucrose-6-ester
CN102639551B (zh) * 2009-10-12 2016-01-20 塔特和莱利技术有限公司 蔗糖-6-酯的生产方法
WO2011045566A1 (en) 2009-10-12 2011-04-21 Tate & Lyle Public Limited Company Low temperature, single solvent process for the production of sucrose-6-ester
GB2474311B (en) * 2009-10-12 2012-10-17 Tate & Lyle Technology Ltd Low temperature, single solvent process for the production of sucrose-6-ester
US20110087019A1 (en) * 2009-10-12 2011-04-14 Tate & Lyle Technology Limited Process for the production of sucrose-6-ester
US8921540B2 (en) 2009-10-12 2014-12-30 Tate & Lyle Technology Limited Low temperature, single solvent process for the production of sucrose-6-ester
CN101979396A (zh) * 2010-10-13 2011-02-23 南京甘倍加生物科技有限责任公司 蔗糖-6-酯及三氯蔗糖的合成方法
US8796446B2 (en) * 2011-05-10 2014-08-05 Tate & Lyle Technology Limited Extraction of carboxylic acids with tin compounds
GB2504237B (en) * 2011-05-10 2018-12-12 Tate & Lyle Tech Ltd Extraction of carboxylic acids with tin compounds
US20120289693A1 (en) * 2011-05-10 2012-11-15 Tate & Lyle Technology Limited Extraction of Carboxylic Acids with Tin Compounds
WO2012153128A1 (en) 2011-05-10 2012-11-15 Tate & Lyle Technology Limited Extraction of carboxylic acids with tin compounds
CN102627675A (zh) * 2012-03-29 2012-08-08 湖北益泰药业有限公司 一种制备蔗糖-6-酯的方法
CN103130843A (zh) * 2013-01-21 2013-06-05 溧阳维信生物科技有限公司 蔗糖制备蔗糖-6-乙酯过程中二丁基氧化锡的回收再利用的方法
CN104098617A (zh) * 2013-04-08 2014-10-15 南京工业大学 一种蔗糖-6-乙酸酯的制备方法
WO2015092374A1 (en) 2013-12-16 2015-06-25 Tate & Lyle Technology Limited Chlorination of sucrose-6-esters
US10227367B2 (en) 2013-12-16 2019-03-12 Tate & Lyle Technology Limited Chlorination of sucrose-6-esters
US10081651B2 (en) 2014-08-08 2018-09-25 Tate & Lyle Technology Limited Chlorination of sucrose-6-esters
WO2016020635A1 (en) 2014-08-08 2016-02-11 Tate & Lyle Technology Limited Chlorination of sucrose-6-esters
CN104387427A (zh) * 2014-10-30 2015-03-04 安徽金禾实业股份有限公司 一种三氯蔗糖的生产方法
US10179760B2 (en) 2015-03-17 2019-01-15 Tate & Lyle Technology Limited DMF distillation
CN105111246A (zh) * 2015-08-22 2015-12-02 安徽金禾实业股份有限公司 三氯蔗糖生产中有机锡的回收方法
CN105111246B (zh) * 2015-08-22 2017-11-17 安徽金禾实业股份有限公司 三氯蔗糖生产中有机锡的回收方法
US10899783B2 (en) 2016-06-23 2021-01-26 Tate & Lyle Technology Limited Liquid-liquid extraction of DMF
US10370398B2 (en) 2016-06-23 2019-08-06 Tate & Lyle Technology Limited Liquid-liquid extraction of DMF
CN108558962A (zh) * 2018-05-22 2018-09-21 山东新和成精化科技有限公司 一种用于合成蔗糖-6-酯的方法
WO2019223485A1 (zh) * 2018-05-22 2019-11-28 山东新和成精化科技有限公司 一种用于合成蔗糖-6-酯的方法
US11142542B2 (en) 2018-05-22 2021-10-12 Zhejiang Nhu Company Ltd. Method for synthesizing sucrose-6-ester
CN110590832A (zh) * 2019-08-15 2019-12-20 安徽金禾实业股份有限公司 三氯蔗糖生产中回收的有机锡乙酸酯的提纯方法
CN111574572A (zh) * 2020-05-22 2020-08-25 安徽金禾实业股份有限公司 一种三氯蔗糖生产中有机锡催化剂连续性制备补充的方法
CN112125938A (zh) * 2020-09-26 2020-12-25 安徽金禾实业股份有限公司 一种从糖渣萃取三氯蔗糖-6-乙酯的方法
CN112495442A (zh) * 2020-12-02 2021-03-16 安徽金禾实业股份有限公司 一种蔗糖-6-乙酯生产中回收制备有机锡催化剂的方法
CN112771059A (zh) * 2020-12-30 2021-05-07 安徽金禾实业股份有限公司 三氯蔗糖的制备方法、粗产品溶液及三氯蔗糖
WO2022141229A1 (zh) * 2020-12-30 2022-07-07 安徽金禾实业股份有限公司 三氯蔗糖的制备方法、粗产品溶液及三氯蔗糖
CN114133411A (zh) * 2021-11-23 2022-03-04 安徽金禾实业股份有限公司 一种三氯蔗糖中萃取絮状物的方法
CN116217635A (zh) * 2023-03-02 2023-06-06 福建桦智工程技术有限公司 一种蔗糖-6-乙酸酯脱酸提纯的方法
CN116217635B (zh) * 2023-03-02 2023-09-01 福建桦智工程技术有限公司 一种蔗糖-6-乙酸酯脱酸提纯的方法

Also Published As

Publication number Publication date
JPH0797387A (ja) 1995-04-11
AU7537791A (en) 1991-10-24
ZA912995B (en) 1992-12-30
EP0455390A3 (en) 1992-07-22
NO911590D0 (no) 1991-04-22
FI97886C (fi) 1997-03-10
PT97432B (pt) 1998-08-31
JP2882548B2 (ja) 1999-04-12
GR910100149A (el) 1992-07-30
EP0455390A2 (en) 1991-11-06
DE69113106D1 (de) 1995-10-26
MX165090B (es) 1992-10-21
IE911343A1 (en) 1991-10-23
YU71591A (sh) 1998-07-10
GR1002083B (en) 1995-12-06
PT97432A (pt) 1992-02-28
IL97891A0 (en) 1992-06-21
DK0455390T3 (da) 1995-11-06
FI97886B (fi) 1996-11-29
AU631062B2 (en) 1992-11-12
DE69113106T2 (de) 1996-04-04
FI911941A0 (fi) 1991-04-22
NO180009B (no) 1996-10-21
NO911590L (no) 1991-10-24
RU2036197C1 (ru) 1995-05-27
ES2080895T3 (es) 1996-02-16
TR25514A (tr) 1993-03-11
PH27407A (en) 1993-06-21
IE68437B1 (en) 1996-06-12
CA2040933C (en) 2002-01-29
KR910018391A (ko) 1991-11-30
KR0176972B1 (ko) 1999-05-15
FI911941A (fi) 1991-10-24
CA2040933A1 (en) 1991-10-24
NO180009C (no) 1997-01-29
TW197443B (es) 1993-01-01
IL97891A (en) 1995-07-31
EP0455390B1 (en) 1995-09-20
NZ237765A (en) 1993-05-26
YU48759B (en) 1999-11-22

Similar Documents

Publication Publication Date Title
US5034551A (en) Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds
US5023329A (en) Sucrose-6-ester production process
US5470969A (en) Catalyzed sucrose-6-ester process
US4950746A (en) Process for synthesizing sucrose derivatives by regioselective reaction
CA2038740C (en) Selective 6-acylation of sucrose mediated by cyclic adducts of dialkyltin oxides and diols
JPH04225993A (ja) サツカロース−６−エステルの製造法
US8921540B2 (en) Low temperature, single solvent process for the production of sucrose-6-ester
EP0475619B1 (en) Catalyzed sucrose-6-ester process
JPH04225992A (ja) 新規白金錯体

Legal Events

Date Code Title Description
AS Assignment

Owner name: NORAMCO, INC., A CORP. OF GA, GEORGIA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:VERNON, NICHOLAS M.;WALKUP, ROBERT E.;REEL/FRAME:005368/0197

Effective date: 19900419

STCF Information on status: patent grant

Free format text: PATENTED CASE

AS Assignment

Owner name: MCNEIL-PPC, INC. A NJ CORPORATION, NEW JERSEY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:NORAMCO, INC., A GA CORPORATION;REEL/FRAME:005715/0078

Effective date: 19910523

FPAY Fee payment

Year of fee payment: 4

FPAY Fee payment

Year of fee payment: 8

REMI Maintenance fee reminder mailed
FPAY Fee payment

Year of fee payment: 12

SULP Surcharge for late payment

Year of fee payment: 11

AS Assignment

Owner name: TATE & LYLE PUBLIC LIMITED COMPANY, UNITED KINGDOM

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:MCNEIL-PPC, INC.;REEL/FRAME:017706/0714

Effective date: 20040527